guys, i'm lost. my car is f*cked and i can't fix it. HELP

[01SVT2894]

guys, i'm dealing with the same problem as before. it seems like my car is missing. i can't figure out why... here is what has been done to try to fix the car, and had no effect...

-new fuel filter
-cleaned IAC
-swapped in a known good IAC
-cleaned EGR
-swapped in a good EGR
-new IAC gasket
-new lower intake gaskets
-new upper intake gasket
-swapped in known good TPS
-put stock TPS back on and made sure the voltage is correct
-cleaned MAF
-new plugs
-new plug wires
-bypassed aftermarket ignition for the stock set up
-new distributor rotor
-new ignition module
-timing has been checked and is good to go


like i said, my RPMs at idle and under load just magically and suddenly drop and then bounce back up. the car just falls flat on it's face. it's been down for several weeks now and i'm completely just discouraged. i'm frustrated as shit and don't know what else to do.

 

[CGoeschel]

fuel pump going out? Just a guess

 

[FoofKiller]

fuel pump going out? Just a guess

Fuel pump, fuel filter, bad distributor, also check to see if your wires are burned anywhere and grounding out.

 

[1BAD93SVT]

replace the ignition module on the distributor. when i had a tune done a few years back, the i.m. was replaced, but was making the car miss. swapped out to the old one and fixed the issue. check your vacuum lines for proper route

 

[01SVT2894]

the ignition module is brand new, i changed it out the other day. didn't fix a thing.

fuel filter is brand new... i just changed it the other day. didn't fix a thing.

 

[kcp203]

Check all vacuum lines. A small crack can cause an intermittent problem.

Also check your ground wire and make sure you don't have any corrosion at either end.

 

[tunedin302]

I think you need to check alll of your wiring. I had the same issue on a non-mustang where I would be driving down the highway and the car would just stop but then magically come back to life. Two wires that went to the ignition module had become bare around a bend in the routing. When the engine would be under load it would move and the two wires would then touch and short out the ignition. Once you can rule out the wiring then you need to make sure you have adequate fuel pressure. In my experience the fuel pump will just cut-off when it goes bad.

 

[1slohawk]

I would check all grounds.

 

[Adower]

Are any of your wires resting on the headers? I had a wire resting on the headers and it burned through just barley. It caused the car to arc on the headers. I know you put you had new wires but I would inspect any of them that are resting on the headers.

 

[MillCreekMafia]

have you checked your actual computer?? i had mine out once when i put my pms in, and i put it back in without the bolt and it didn't have a good connection and i tell you what, i was baffled at the shit my car was doing.

 

[93SVTCobra]

Which car is it and what mods are on it?

 

[9T3SVT]

Diagnose the problem and repair it instead of throwing parts at the car. You are probably over thinking it. Quit wasting your sanity, time, and money. If the problem is beyond your expertise then it's time to take it to a mechanic.

Your answer to every question is "I replaced that" but you haven't given a whole lot of info.

 

[Tank5879]

fuel pump relay???

 

[5liter]

Which car is it and what mods are on it?

Need to know all the mods. I am assuming this is the 93 you are working on?

 

[Red Turtle]

:nono: It looks like you still haven't changed the MAF.... It looks like you cleaned it, but didn't change it. If it is shot, cleaning ain't gonna do anything.

 

[01SVT2894]

:nono: It looks like you still haven't changed the MAF.... It looks like you cleaned it, but didn't change it. If it is shot, cleaning ain't gonna do anything.

a MAF is going to cost too much to shoot in the dark here. is there any way to test the MAF to see if it's bad?

 

[Lightning&Mach1]

Could be the pickup in the distributor. I've had a few 5.0s act like this and that was the problem.

 

[SRV1]

While the car is running, wiggle the wires that go into the coil.

James

 

[01cobravortech]

a MAF is going to cost too much to shoot in the dark here. is there any way to test the MAF to see if it's bad?

If your MAF is bad you aren't necessarily going to get a code. It could be as simple as that.

 

[1BAD93SVT]

make sure the plug wires are routed correctly